Electronic circuits can be damaged by excess voltage and accordingly a voltage regulator may be used between a power source and a circuit requiring voltage protection. Some electronic circuits continue to function fully when supplied with less than the rated voltage and ideally require that the voltage regulator provides a direct path.
Voltage regulators, by their very nature, are a drain on the main power source. One existing technology is the low drop out regulator (LDO), which provides series voltage regulation with a small voltage difference across the device. Such regulators may be used with a power source whose voltage is only slightly above the rated value of the regulator. Accordingly, such regulators can keep power losses to a minimum during operation.
Certain types of battery operated equipment operate in an intermittent manner, with short bursts of activity interspersed by longer periods of inactivity. For such types of equipment, the sum of the power losses during operation can be much less than the amount of power lost when the device is switched off, in a standby mode or otherwise operating in a state where the circuit is only drawing a small amount of current.